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Mimo nierównomiernego rozwoju krajów kontynentu produkty rybołówstwa i akwakultury są obecne na rynkach UE. Głównymi producentami ryb z połowów morskich są: Maroko, Senegal i RPA, natomiast z połowów słodkowodnych Tanzania, Uganda, Egipt i Nigeria. Afryka zwiększyła jednak swój wkład w światową produkcję akwakultury z 1,2 do 2,2% w ciągu ostatnich dziesięciu lat, głównie w wyniku szybkiego rozwoju hodowli ryb słodkowodnych w Afryce subsaharyjskiej. Główni producenci to Nigeria, Egipt i Uganda. Oprócz tradycyjnie importowanych, głównie z RPA i Namibii, gatunków morszczuków, na rynku UE mogą pojawić się nowe gatunki zwierząt wodnych - nie tylko ryb. Kilka ostrzeżeń umieszczonych w systemie RASFF wskazuje na wciąż istniejący problem jakości administracji odpowiedzialnej w krajach Afryki za nadzór weterynaryjny i jakość produktów w eksporcie na rynki krajów UE.
Ryby oraz produkty rybołówstwa to w ujęciu wartościowym ok. 10% ogólnego eksportu produktów rolnych i 1% światowego handlu towarami. Wprowadzenie systemu RASFF umożliwia skuteczną identyfikację i dystrybucję informacji o zagrożeniach ze strony mikroflory, metali ciężkich bądź zafałszowań produktów. Ta ostatnia grupa ma istotne znaczenie dla ukierunkowania monitoringu i systemów kontroli zdrowotności produktów na wszystkich etapach łańcucha żywnościowego. Z danych RASFF wynika, iż liczba wszystkich typów ostrzeżeń zarejestrowanych w systemie w przypadku ryb oraz produktów rybnych rosła do 2011 r. Następnie w latach 2011-2015 ustabilizowała się na poziomie 300 zgłoszeń na rok, co w 2014 r. stanowiło 12% spośród wszystkich zgłoszeń odnotowanych w RASFF. Analiza powiadomień RASFF wskazuje również na dotychczas nieznane zagrożenia, ujawniające nowe kierunki w obrocie produktami rybołówstwa i akwakultury, które stwarzają nieoszacowane dotychczas zagrożenia dla zdrowia człowieka (alergeny, dodatki funkcjonalne, pozostałości leków, chemikalia środowiskowe).
Exotic species of acipenserid fishes have been frequently encountered in the commercial catches of the Baltic Sea, since the early 1990s. Such sightings are rarely reflected as published records. The present paper provides detailed descriptions of two specimens of Russian sturgeons, Acipenser gueldenstaedtii caught in the Exclusive Polish Economic Zone of the Baltic Sea.
The first occurrence of striped red mullet Mullus surmuletus in the Pomeranian Bay (in 2007) and the occurrence of three very rarely noted species (tub gurnard Chelidonichthys lucerna, Atlantic horse mackerel Trachurus trachurus, thicklip grey mullet Chelon labrosus) collected in 2007–2008 in the Pomeranian Bay, Szczecin Lagoon and Lake Dąbie are reported. Their expansion is probably due to increased sea temperatures resulting from climate change, as well as the inflow of saline water. The ‘visitors’ hosted eight pathogens from four taxonomic groups: Protozoa, Nematoda, Acanthocephala and Mollusca. Nematodes, the most numerous ones, were found in three host species. All the parasite species were new for the hosts examined; only the larvae of the acanthocephalan Corynosoma strumosum had already been recorded in one of the hosts (Chelidonichthys lucerna). The stomachs of almost all the fish examined were empty, but the species composition of the parasite fauna found showed that the fish must have ingested some food in the Pomeranian Bay.
We report on the first occurrence of Chelon labrosus in a Polish estuary. One Ch. labrosus was caught with a fyke net in the northern part of Lake Dąbie (Odra estuary) on 14 November 2007. It measured 266.92 mm in overall length and weighed 176.8 g. The fish’s metric and meristic characters, age by scale, condition, sex and maturity stage (Maier’s scale) were determined.
Background. Genetic traceability of seafood as well as population identification using molecular methods provide useful information about the fish origin and are important for protection of overfished populations, as well as for monitoring illegal, unreported, and unregulated (IUU) fisheries. The presently reported study focused on Indian mackerel, Rastrelliger kanagurta (Cuvier, 1816)—a pelagic species with a wide range of distribution—especially important for many tropical countries, such as India, Philippines, and Thailand. This paper is the first part of a larger project: ”Development of a genetic-based system for identification of food products from fisheries and aquaculture introduced to the European Union customs area”. Materials and Methods. Samples consisting of fin fragments of Indian mackerel were obtained from local markets in Thailand (MTH), Vietnam (SVN), Cambodia (SKH), and Madagascar (SMG) within 2012–2013. Two genes were analysed: nuclear rhodopsin gene (RH1) and mitochondrial D-loop (D-loop) region through RFLP analysis simulation and sequencing. Additionally, the samples from Cambodia and Madagascar were analysed with eight microsatellite loci (SSR). The data processing was aided by GenAlEx 6.5 and GeneClass2 software. Results. A comparison of the RH1 gene section revealed a total homology among the studied samples. A comparative analysis of D-loop sequences in the studied groups revealed intrapopulational diversity for MTH-, SKH-, SMG-, and SVN samples, at the level of 1, 1, 0.5, and 0.6 percentage points, respectively. Furthermore, the D-loop sequences identified a characteristic restriction site for SMG population. Based on the allele frequencies, we randomly assigned selected individuals to their original populations. GeneClass2 software correctly assigned only 16 out of 21 individuals to either the Cambodian or the Madagascar population, which jointly constituted 76% of all samples. We demonstrated, using AMOVA and GenAlEx 6.5, that the highest level of variability occurred among individuals within the respective populations, while the lowest interpopulation diversity was between the SMG and SKH populations. Conclusion. Our results may help the relevant authorities in the countries of the European Union to identify Indian mackerel and especially its products and trace them to the respective locality. Our findings may also be used for species-specific conservation measures hopefully undertaken by fisheries authorities of the countries where we took our samples. Results on other fish species, prepared in the frames of the same project, will be presented in other papers that will follow soon.
Background. Asian pangasiids (Actinopterygii: Siluriformes: Pangasiidae), commonly referred to as “panga”, have recently became an important item on the European fish markets. The fish are currently imported from south-east Asia but the growing consumers’ demand is likely to motivate European fish growers to culture the “panga” locally. This in turn could bring about unforeseeable consequences for the aquatic environment. The presently reported study provides the first record of a pangasiid fish (two specimens) from the European natural waters. We attempted to identify the fish through complex morphometric procedures and to study all their parasites, thus determining their potential threat for the environment. Materials and Methods. Two specimens of pangasiid fish were captured in a pond, in the city of Szczecin, Poland. The fish were examined following procedures commonly accepted in morphological studies yielding detailed measurements. The key structures were described and illustrated (e.g., the shape of dentition on both the vomerine and palatine plates). The measurements were taken with an electronic calliper and a dissecting microscope (Nikon SMZ 1000), coupled with the Lucia Measurement System. Additionally, during necropsy, selected organs were checked for the presence of parasites. Results. One of the fish specimens hosted the monogenoid parasite, Thaparocleidus caecus, that has never been found in Europe. Metric and meristic characters of fish studied, as well as the presence of monogenoid T. caecus suggest that the fish found were representatives of Pangasianodon hypophthalmus, however, some features, especially those related to the ratio between fins and body or total length, differ markedly from the species description. Comparative analysis suggested that the two specimens collected in Szczecin are hybrids, most likely of P. hypophthalmus with other species, of unknown origin, presumably imported from Thailand. Conclusion. The specific identity of pangasiids imported alive to Europe should be monitored in the future. Additional genetic studies are needed. The monogenoid parasite found on the fish studied poses no threat to the native ichthyofauna (because of its very narrow host-specificity).
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